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New Dinosaur Species Discovered In China Takes Long Necks To A Whole New Level

01/29/2015 2:59 pm EST

A new dinosaur species discovered in China is being called “extreme”–and for good reason. The dino’s neck is so long that it makes up more than half of the creature’s huge 49-foot-long body.

The dinosaur–dubbed Qijianglong guokr, or “dragon of Qijiang“–is believed to have roamed Asia about 160 million years ago in the Late Jurassic Period. It was identified by skull and vertebrae fossils unearthed in 2006 by construction workers near Quiang City in the southern part of the country.

Qijianglong is believed to belong to mamenchisauridae, a family of dinosaurs known for extremely long necks. But unlike most mamenchisaurids, Qijianglong had vertebrae that were hollow and so tightly linked that the dinosaur’s neck is believed to have been stiff like a construction crane.

Purgatorius has been considered a plausible ancestor for primates since it was discovered, but this fossil mammal has been known only from teeth and jaw fragments. We attribute to Purgatorius the first (to our knowledge) nondental remains (ankle bones) which were discovered in the same ∼65-million-year-old deposits as dentitions of this putative primate. This attribution is based mainly on size and unique anatomical specializations known among living euarchontan mammals (primates, treeshrews, colugos) and fossil plesiadapiforms.

Results of phylogenetic analyses that incorporate new data from these fossils support Purgatorius as the geologically oldest known primate. These recently discovered tarsals have specialized features for mobility and provide the oldest fossil evidence that suggests arboreality played a key role in earliest primate evolution.

Abstract

Earliest Paleocene Purgatorius often is regarded as the geologically oldest primate, but it has been known only from fossilized dentitions since it was first described half a century ago. The dentition of Purgatorius is more primitive than those of all known living and fossil primates, leading some researchers to suggest that it lies near the ancestry of all other primates; however, others have questioned its affinities to primates or even to placental mammals.

Here we report the first (to our knowledge) nondental remains (tarsal bones) attributed to Purgatorius from the same earliest Paleocene deposits that have yielded numerous fossil dentitions of this poorly known mammal. Three independent phylogenetic analyses that incorporate new data from these fossils support primate affinities of Purgatorius among euarchontan mammals (primates, treeshrews, and colugos).

Astragali and calcanei attributed to Purgatorius indicate a mobile ankle typical of arboreal euarchontan mammals generally and of Paleocene and Eocene plesiadapiforms specifically and provide the earliest fossil evidence of arboreality in primates and other euarchontan mammals. Postcranial specializations for arboreality in the earliest primates likely played a key role in the evolutionary success of this mammalian radiation in the Paleocene.

This fight was a real fight that was recorded in bones! The Utahraptor was attacking such an armed dinosaur cause it was about to die by lack of food during a drought. And in the end both animals died, the Gastonia died by its wounds which the Utahraptor inflicted on its belly and legs. And the Gastonia died only 10 feet away after walking from the dead Utahraptor.

Reports of what looked like a human arm brought Utah state paleontologist James Kirkland to a particular sandstone hill in 2001. But it turned out that his graduate student had actually found something entirely different — a veritable mass grave of Utahraptor dinosaurs. Now they’ve found the remains of six individual dinosaurs, and there may still be more inside of the 9-ton sandstone block they’re excavating.

That “arm” was actually a foot, and the fossil bits just kept coming. The site is now the largest find ever for this particular species, which was a large, feathered cousin to the more familiar Velociraptor. It seems that these unfortunate raptors were trapped in quicksand — sand so heavy with water that it loses much of the friction between its grains. Quicksand isn’t actually the deathtrap for humans that cinema would have us believe, but for a frightened animal who couldn’t gain purchase, it might have meant suffocation or slow starvation — or simply getting stuck until a bigger predator arrived to finish the job.

Brian Switek for National Geographic reports that a plant-eating dinosaur was found at the site, too, which could mean that the raptors all died at the same time while hunting the trapped creature. That would be exciting, because despite their depiction as pack hunters in the “Jurassic Park” films, we don’t have much evidence about whether dinosaurs like these came in droves or hunted solo.

If the researchers can show that the raptors grew tangled up together as they struggled to get free, or find evidence that the same weather patterns affected their bones when they died, it would add weight to the notion that raptors liked to rumble in gangs.

A high school student from southern Sweden who discovered the remains of Sweden’s first known carnivorous dinosaur has been speaking about his discovery.

Clarence Lagerstam, who lives in Kristianstad in Skåne found a small piece of bone when he was searching in an area popular with fish and reptile fossil hunters.

“I did not think there would be more, but then I found more smaller fragments and I became more and more excited,” he told Swedish news network SVT.

Experts believe the bones are the remains of a large carnivorous dinosaur that lived on what is now Swedish soil around 80 million years ago when the region had a warm climate, similar to that in the Mediterranean today.

Lagerstam has kept his finding in a black cardboard box, wrapped in paper towels, but has opened it several times this week to show off what he calls his “dream” finding to the Swedish media.

Johan Lindgren, a paleontologist and researcher at nearby Lund University says it is “fantastic” that the schoolboy made the finding in an area where experts have been searching for fossils for 150 years.

“You can never stop being fascinated by what is actually out there in the Swedish soil,” he told SVT.

Lagerstram says he first became interested in fossils and dinosaurs when he watched the movie Jurassic Park and plans to continue with his interest.

“It’s a great feeling to be able to read about ancient ecosystems and to learn what prehistoric animals looked like, how they lived and how they interacted with their environment”.

Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation.

Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs) calculated for 10% cartilage—the most reasonable estimate—appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

Introduction

The habitual posture of the necks of sauropod dinosaurs has been controversial ever since their body shape has been understood. Both elevated and more horizontal postures have been depicted, sometimes even in the same images—for example, Knight’s classic 1897 painting of Apatosaurus and Diplodocus (Fig. 1). See the introduction to Taylor & Wedel (2013) for a more comprehensive historical overview.

Figure 1: Charles R. Knight’s famous 1897 painting of sauropods, which were then considered amphibious.
In the foreground, Apatosaurus (“Brontosaurus” of his usage) wades in a lake, its neck erect. In the background, Diplodocus wanders on the shore, its neck held low and horizontal. These differences in posture may not represent different perceptions of the habitual behaviour of these different taxa, merely the postures these individuals happened to adopt at a particular moment.

We are increasingly confronted with the consequences of global warming and the loss of bio-diversity. The more we understand and appreciate the wonder of nature, the better we are able to sustain our life on this planet. This is where the T-Rex comes in. Can you imagine another creature that has been able to better capture the imagination of kids? This is why we decided to go on an epic journey to find a real T-Rex and bring it to Europe. We believe that through telling the story of this T-Rex and its excavation we can get more kids to experience the wonder of life on this planet.

About one and a half years from now, for the first time ever a skeleton of a Tyrannosaurus rex will move to outside the United States, namely to the Netherlands. Naturalis Biodiversity Center in Leiden has received 5 million to buy a skeleton of the dinosaur. It was excavated in 2013 in the US state Montana.

Last year, scientists at the research institute and natural history museum excavated large parts of the Tyrannosaurus rex in Montana. It is a well-preserved skeleton of a then probably 30 years old female. …